Antiphospholipid syndrome (APS), first described in 1983, is now recognized as a major thrombotic syndrome with clinical features that range from deep vein thrombosis (DVT), chronic leg ulcers, recurrent miscarriages, headache, heart attacks, renal vein and artery thrombosis, to pulmonary embolism and even pulmonary hypertension, associated with antiphospholipid antibodies (e.g., cardiolipin). Phospholipids are lipids or fats that are insoluble in hydrophilic environments. Current immunoassay technology uses hydrophobic attractions to bind phospholipids to the hydrophobic surface of a microtiter plate. The conventional enzyme-linked immunosorbent assay (ELISA) for anti-cardiolipin antibodies uses cardiolipin that is passively coated on a solid phase, onto which various cofactor proteins are adsorbed. The configuration of this format is able to detect, but is not efficient in differentiating, a heterogeneous group of anti-cardiolipin antibodies that include cofactor-dependent and independent antibodies against cardiolipin. Moreover, the passive configuration is difficult to reproducibly manufacture and is not stable in an aqueous environment. The detection of these anti-cardiolipin antibodies is influenced by the amount and quality of bovine serum and the subsequent fluctuation of the level of cofactor proteins added to the assay. In addition, the passive configuration of the cofactor protein-phospholipid complexes will not withstand the presence of detergents such as Tween20 and CHAPS, which are commonly added to the assay to reduce non-specific binding and to enhance sensitivity and specificity. Detergents interfere in anti-phospholipid immunoassays by solubilizing the lipid bound to the solid phase and thereby causing a loss in signal (see WO91100138, US2004096903). Thus, users have frequently reported variability in assays for anti-cardiolipin antibodies. The present invention solves this and other needs.